Noisy wheel covers are very objectionable to car owners. In order to test wheel covers for noise, the wheel covers must be tested when mounted on a wheel and the wheel is rotating. Wheel covers have been tested in the past but with results that have not been entirely satisfactory. It is important that the testing take place in an environment which is protected from extraneous or random outside noise. It is also desirable that the testing machine be capable of testing wheel covers on wheels of varying sizes and with equipment for detecting and transmitting any noise produced during testing to persons located some distance from the test machine.
In accordance with the present invention, the test wheel is mounted in a compartment and preferably is driven in rotation by a drive wheel mounted outside the compartment but in frictional peripheral contact with a tire on the test wheel through an opening in the compartment. A microphone is supported in the compartment of the test wheel for detecting and transmitting wheel cover noise incident to rotation of the test wheel. Preferably, a support is provided for the microphone comprising a first track extending in one direction and a second track perpendicular to the first track and movable along the first track. The microphone is mounted for movement along the second track so that placement of the microphone in a desired position along the second track and the second track in a desired position along the first track will enable the microphone to be accurately positioned where desired to best monitor noise when the wheel and wheel cover are rotated.
Preferably, the drive wheel is mounted in a separate compartment so that the noise, if any, incidental to operation of the drive wheel will not affect the test results.
It is also preferable that both compartments be mounted within a cage supported on isolator pads so that any vibration occasioned by the operation of the test apparatus will be dampened.
Preferably, the compartment for the test wheel has a door which can be opened to load and unload a test wheel, and a window for viewing which can be opened to adjust the microphone.
One object of this invention is to provide a wheel cover noise testing machine having the foregoing features.
Another object is to provide a wheel cover testing machine which is composed of a relatively few simple parts, is rugged and durable in use, and can be relatively inexpensively manufactured and assembled.
These and other objects, features and advantages of the invention will become more apparent as the following description proceeds, especially when considered with the accompanying drawings.